The present invention is directed to integrated circuits and their processing for the manufacture of semiconductor devices. More particularly, the invention provides a method and apparatus for securing a ball grid array (BGA) package so that decapsulation of the package can occur. Merely by way of example, the invention can be used for BGA packages of varying dimensions without having to rely on a separate decapsulation holder for each package size. But it would be recognized that the invention has a much broader range of applicability.
Integrated circuits or “ICs” have evolved from a handful of interconnected devices fabricated on a single chip of silicon to millions of devices. Current ICs provide performance and complexity far beyond what was originally imagined. In order to achieve improvements in complexity and circuit density (i.e., the number of devices capable of being packed onto a given chip area), the size of the smallest device feature, also known as the device “geometry”, has become smaller with each generation of ICs. Semiconductor devices are now being fabricated with features less than a quarter of a micron across.
Increasing circuit density has not only improved the complexity and performance of ICs but has also provided lower cost parts to the consumer. An IC fabrication facility can cost hundreds of millions, or even billions, of dollars. Each fabrication facility will have a certain throughput of wafers, and each wafer will have a certain number of ICs on it. Therefore, by making the individual devices of an IC smaller, more devices may be fabricated on each wafer, thus increasing the output of the fabrication facility. After the individual devices have been manufactured within the IC fabrication facility, the devices must be tested and packaged to ensure the reliability of the manufactured circuits. One technique that can be used to package the manufactured circuits is in a ball grid array (BGA) package, where the circuit is encapsulated within a molding material to protect the circuit from exposure or undesired contact. Solder balls are attached to the base of the package to provide a reliable electrical connection from the integrated circuit.
After a packaging process has been performed on an integrated circuit, it may be necessary to decapsulate or open the package to facilitate analysis or electrical examination of the integrated circuit or the internal features of the package. For example, thermal testing may be performed on the exposed circuit after decapsulation to determine if hotspots are present on the chip after the circuit has been cycled in operation. Another reason for decapsulation of a package can be to check for crossed wires or pinholes within the integrated circuit. A decapsulation process can consist of a purely mechanical process such as prying or cutting away the encapsulant layer, or may be performed using a chemical etch, plasma etch, or thermomechanical removal process to remove the encapsulant layer.
One component of the decapsulation process is to ensure that the BGA package is properly secured and oriented with the decapsulation equipment so that removal can properly occur without any damage to the integrated circuit. A decapsulation holder can be used for this process. However, BGA packages are often manufactured in different sizes to accommodate for the different sizes and shapes of integrated circuits. Different decapsulation holders are used for different sizes of BGA packages, leading to an increased cost as a range of decapsulation holders must be maintained at the IC fabrication facility. Having different decapsulation holders can also lead to longer processing time for circuits, as the decapsulation holder must be switched out for integrated circuits of different sizes before the decapsulation process can occur.
From the above, it is seen that an improved method and apparatus for the decapsulation for semiconductor packages is desired.